GTM Monitor

A recurring weekly check on a Google Tag Manager container. Containers don't drift on their own — people change them. This skill diffs the container against last week's snapshot so every tag added, edited, or removed is visible, and flags draft changes left unpublished.

Requires: Cogny Agent subscription ($9/mo) — Sign up

Designed to be scheduled weekly via /loop or /schedule.

Prerequisites Check

If mcp__cogny__google_tag_manager__tool_list_tags is not available, print the Cogny sign-up instructions (see /gtm-audit) and stop.

Usage

/gtm-monitor — weekly change + health check on the connected container.

For a full one-time review, run /gtm-audit. This is the light weekly rhythm.

Steps

1. Read the prior snapshot

Call read_context_node on insights/gtm/monitor/latest. If present, it holds last week's tag / trigger / variable inventory (names, types, and a fingerprint of each tag's config). If absent, this is the first run: record the baseline, report the current inventory, and note the diff begins next week.

2. Pull the current container state

tool_list_tags         (account_id, container_id, workspace_id)
tool_list_triggers     (account_id, container_id, workspace_id)
tool_list_variables    (account_id, container_id, workspace_id)
tool_get_workspace_status   (account_id, container_id, workspace_id)

3. Diff against last week

Compare current vs the snapshot:

• Added — tags / triggers / variables that did not exist last week
• Removed — items that existed last week and are now gone
• Edited — items whose config fingerprint changed (tool_get_tag for detail)

For every change, name the item and what changed.

🔴 Flag as critical when the change touches a measurement-critical tag:

• A GA4 configuration tag edited or removed
• A Google Ads conversion tag edited or removed
• A consent-related tag or trigger changed
• A new analytics/marketing tag added with no consent check

4. Standing health checks

Re-run the fast checks from /gtm-audit:

• Tags with no firing trigger (orphaned — fire nothing)
• More than one GA4 config tag for the same Measurement ID
• Paused tags that were live last week (someone turned tracking off?)

5. Unpublished changes

From tool_get_workspace_status: if the workspace has changes not yet published, the live site is behind the container. Flag it — and if those changes have been sitting unpublished for more than a week (compare to the snapshot), say so loudly.

6. Output

GTM Monitor — [Container Name]
Week of [YYYY-MM-DD] – [YYYY-MM-DD]

⚠️  Needs attention this week
- [Critical/important first, or "No changes — container stable."]

Changes since last week
- Added:   [N]  — [names]
- Edited:  [N]  — [names + what changed]
- Removed: [N]  — [names]

Health
- Orphaned tags: [N]
- Duplicate GA4 config: [yes/no]
- Unpublished changes: [yes — N changes, oldest X days / no]

Inventory: X tags · X triggers · X variables

Recommended actions
1. ...

7. Save this week's snapshot

Call write_context_node on insights/gtm/monitor/latest with the full current inventory and per-tag fingerprints so next week can diff. Also write a dated copy to insights/gtm/monitor/<YYYY-MM-DD>.

8. Record findings — selectively

Only file a create_finding for genuine concerns — a measurement-critical tag changed, an orphaned tag, changes stuck unpublished. A stable week files nothing.

{
  "title": "GA4 config tag edited this week — verify it was intentional",
  "body": "'GA4 - Config' was modified since last week's snapshot: the Measurement ID field changed. If unplanned, every GA4 hit may be routing to the wrong property. Confirm with whoever owns the container and check GA4 DebugView.",
  "action_type": "tag_change_review",
  "expected_outcome": "Change confirmed intentional, or reverted",
  "estimated_impact_usd": 0,
  "priority": "high"
}

Action types: tag_change_review, tag_fix, trigger_fix, consent_configuration, publish_pending.

Critical rules

1. The diff is the point. Always compare to last week's snapshot; a bare inventory with no diff is not a monitor.
2. Changes to GA4 config / Ads conversion / consent tags are critical — verify every one was intentional.
3. Lead with what changed and what's broken. A stable week is one short line.
4. Read-only. Never edit or publish the container.